Process for breaking petroleum emulsions



Patented July 18, 1944 PROCESS FOR BREAKING PETROLEUM EEWULSIONS Melvin De Groote, University City, and Bernhard Keiser, Webster Groves, Mo., asslgnors to Petrolite Corporation, Ltd., Wilmington, Del., a

corporation of Delaware No Drawing. Application June 15, 1942, Serial No. 447,152

8 Claims.

This invention relates primarily to the resolution of petroleum emulsions.

The main object of our invention is to.pro

. vide a novel process for resolving petrolemn emulsions of the water-in-oil type, that are commonly referred to as cut oil," "roily oil, emulsified oil, etc., and which comprise fine droplets of naturally-occurring waters or brines dispersed in a more or less permanent state throughout the oil which constitutes the continuous phase of the emulsion.

Another object is to provid an economical and rapid process for separating emulsions which have 'been prepared under controlled conditions from mineral oil, such as crude petroleum and relatively soft waters or weak brines. Controlled emulsiflcation and subsequent demulsification under the conditions just mentioned is of significant value in removing impurities, particularly inorganic salts, from pipelin oil.

We have discovered that if one oxyalkylatesv glycerol so as to introduce at least three oxyalkylene radicals for each hydroxyl group, and if the product so obtained is reacted with a polybasic carboxy acid having not over eight carbon atoms, and in such a manner as to ield a fractional ester, due to the presence of at least one free carboxyl radical, one can then esterify said acidic material or intermediate product with at least one mole of an alcoholic compound of the type herein described to give a variety of new compositions of matter which are eflicient demulsifiers for crude oil emulsions.

The compounds used as the demulsifier in our herein described process may be produced in any suitable manner, but are usually manufactured by following one of two-general procedures. In one of said procedures oxyalkylated glycerol, which is, in essence, a polyhydric alcohol, is reacted witha polybasic acid so as to give an acidic material, or intermediate product, which, in turn, is reacted with an alcoholic body of the kind hereinaifer described, and momentarily indicated by the formula R1(OH) m. Generically, the alcoholic body herein contemplated may be consid- Glycerol may be conveniently indicated by the following formula:

0H 01115 01! on If treated with an oxyalkylatingagent, and momentarily consideration will be limited to an oxyethylating agent, one may obtain an oxyethylated glycerol of the following formula:

in which the value of 12. may vary from 3 to 10 and all the values of n need not be identical. If a polybasic carboxy acid be indicated by the formula:

coon

coon

then the acyclic reaction product of one mole of oxyethylated glycerol and one mole of a polybaslc carboxy acid may be indicated by the following formula:

(oimowoocmcoomw in which n" has the value of one or two. Similarly, if two moles of the polybasic acid be used, then the compound may be indicated by the following formula:

(cniimnooomcoomw cimoi-(cinlowoocR(oo0H Likewise, if three moles of a polybasic acid are employed, the compound may be indicated by the following formula If a fractional ester of the kind exemplified by the three preceding formulas is reacted with one or more moles of an alcohol of the kind previously described in a generic sense as R1(OH)1n,

then obviously, one may obtain a material of. the type indicated by the following formula:

in which :1: is 0, 1 or 2, y is 0,1or 2, and z is 1,2

' or 3,and .t' is or 1, and y is 1 or 2.

It has been previously stated that compounds of the type herein contemplated may be obtained by oxyalkylating agents, withoutbeing limited to ethylene oxide. Suitableoxyalkylating agents include ethylene oxide, propylene oxide, butylene oxide and glycid, which, although not included, strictly speaking, by the unitary structure Cal-I250,

.aminoamide. Thus, the preceding formula may be rewritten in its broader scope, as follows:

[( HHMOH 0 00Z)-]= CzH50a-[(CnHzn0)'/H] in which n replaces the numbers 2, 3- or 4, Z includes the acidic hydrogen atom itself. In the above formula, and hereafter, for convenience R1 is intended to include any hydroxyl groups that remain. i

If the compounds herein contemplated are obtained under usual conditions, at the lowest temperatures, then the monomeric form is most likely to result. The production of the compounds herein contemplated is the result of one or more esterification steps. As is well known, esterification procedures can be carried out in various manners; but generally speaking, esterifications can be carried out at the lowest feasible temperatures by using one of several procedures. One procedure is to pass an inert, dried gas through the mass to be esterified, and have present at the same time a small amount of a catalyst, such as dried HCl gas, a dried sulfonicacid, or the like. Another and better procedure, in many instances, is to employ the vapors of a suitable-liquid, so as to remove any water formed and condense both the vapors of the liquid employed and the water in such a manner as to trap out the water and return the liquid to the reacting vessel. This procedure is commonly employed in the arts, and for convenience, reference is made to U. S. Patent No. 2,264,759, dated Dec. 2, 1941, to Paul C. Jones.

Referring again to the last two formulas indicating the compounds under consideration, it can .be readily understood that such com ounds, in numerous instances, have the property of polyfunctionality. In view of this fact, where there is at least one residual carboxyl and at least one residual hydroxyl, one would expect that under suitable conditions, instead of obtaining the monomeric compounds indicated, one would, in

. reality, obtain a polymer in the sense, for example, that polyethylene glycols represent a polymer common in the arts concerned with materials of i this type, it is so adopted here. Thus, reference in the appended claims to polymers is intended to include the self-esterification products of the monomeric compounds.

In view of what has been said, and in view of the recognized hydrophile properties of the recurring oxyalkylene linkages, particularly the oxyethylene linkage, it is apparent that the materials herein contemplated may vary from compounds which are clearly water-soluble through self-emulsifying oils, to materials which are balsam-like and sub-resinous or semi-resinous in nature. The compounds may vary from mono- .mers to polymers, in which the unitary structure appears a number of times, for instance, 10 or 12 times. It is to be noted that true resins, i. e., truly insoluble materials of a hard plastic nature, are not herein included. In other words, the polymerized compounds are soluble to a fairly definite extent, for instance, at least 5% in some solvents, such as water, alcohol, benzene, dichloroethyl ether, acetone, cresylic acid, acetic acid, ethyl acetate, dioxane, or the like. This is simply another way of stating that the polymerized product contemplated must be of the subresinous type, which is commonly referred to as an A resin, or a B resin, as distinguished from a C resin, which is a highly infusible, insoluble resin (see Ellis, Chemistry of Synthetic Resins (1935), pages 862, et seq.).

Reviewing the form as presented, it is obvious that one may obtain compounds within the scope disclosed, which contain neither a free hydroxyl nor a free carboxyl group, and one may also obtain a compound of the type in which there is present at least one free carboxyl, or at least one free hydroxyl, or both. The word polar has sometimes been used in the arts in this particular sense to indicate the presence of at least one free hydroxyl group, or at least one free carboxyl group, or both. In the case of thefree carboxyl group, the carboxylic hydrogen atom may, of course, be replaced by any ionizable hydrogen atom equivalent, such, for example, as a metal,

an ammonium radical, a substituted ammonium radical, etc. In the hereto appended claims the word polar is used in this specificsense.

We are aware that compounds similar to those contemplated in the present instance may be derived from polyhydroxylated compounds having more than three hydroxyl groups. For instance, they may be derived from acyclic diglycerol, triglycerol, tetraglycerol, mixed polyglycerols, mannitol, sorbitol, various hexitols, dulcitol, pentaerythritol, erythritol monoether, and other similar compounds. Such particular types in which higher hydroxylated materials are subjected to oxyalkyl- 'ationand then employed in the same manner as oxyalkylated glycerol is employed in the present instance, are'not contemplated in this specific cas,,.although attention is directed to the same.

Reference is also made to other oxyalkylated sorbitan, mannitan, 'dipentaasaaeoc compounds which may be used as reactants to replace oxyalkylated glycerol, or oxyalkylated ethylene glycol, which latter reactant is described in a co-pending application hereinafter referred to. The reactants thus contemplated include the type in which there is an amino or amido nitrogen atom, particularly when present in a low molal type of compound prior to oxyalkylation, reference being made to polyhydroxylated materials, including those having two or three hydroxyl groups, as well as those having more than three hydroxyl groups. For instance, the oxyalkylated derivatives, particularly the oxyethylated derivatives of ethyldiethanolamine, bis(hydroxyethyDacetamide, the acetamide of tris(hydroxymethyDaminomethane, tetrahydroxylated ethylene diamine, etc. Compounds may also be derived from cyclic diglycerol and th like.

Furthermore, for convenience, attention is directed to a somewhat similar class of materials which are described in U. S. Patent No. 2,295,163, dated September 8, 1942, to De Groote and Keiser. Said patent involves the use of the same type of alcoholic bodies for reactants, but is limited, among other things, to the compounds which are essentially symmetrical in nature, for instance, involving the introduction of two alcoholic residues, whereas, in the present instance, one, two, or three, 01 more, might be introduced.

As indicated previously, the polybasic acids employed are limited to the type having not more than eight carbon atoms, for example, oxalic, malonic, succinic, glutaric, adlpic, maleic. and phthalic. Similarly, one may employ acids such as fumaric, glutaconic, and various others, such as citric, malic, tartaric, and the like. The selection of the particular tribasic or dibasic acid employed, is usually concerned largely with the convenience of manufacture of the finished ester, and also the price of the reactants. Generally speaking, phthalic acid or anhydride tends to produce resinous materials, and greater care must be employed if the ultimate or final product be of a sub-resinous type. Specifically, the preferred type of polybasic acid is such as to contain six carbon atoms or less. Generally speaking, the higher the temperature employed, the easier it is to obtain large yields of esterified product. although polymerization may be stimulated. xalio acid may be comparatively cheap, but it decomposes readily at slightlyabove the boiling point of water. For th s reason it is more desirable to use an acid which is more resistant to pyrolysis. Similarly, when a polybasic acid is available in-the form of an anhydride, such anhydride is apt to produce the ester with greater ease than the acid itself. For this reason, maleic anhydride is particularly adaptable, and also, everything else considered, the cost is comparatively low on a per molar basis, even though somewhat higher on a per pound basis. Suocinic acid or the anhydride has many attractive qualities of maleic anhydride. and this is also true of adipic acid. For purposes of brevity, the bulk of the examples hereinafter illustrated will refer to the use of maleic anhydride, although it is understood that any other suitable polybasic acid may be employed. Furthermore, reference is made to derivatives obtained by oxyethylation, although, as previously pointed out, other oxyalkylating agents may be employed.

As far as the range of oxyethylated glycerols employed as reactants is concerned, it is our preference to employ those in which approximately to 24 oxyethylene groups have been introduced Oxvarnxmrsn GLYcsnor.

Example 1 184 pounds of glycerol is mixed with 41%, by weight, of caustic soda solution having a specific gravity of 1.383. The caustic soda acts as a catalyst. The ethylene oxide is added in relatively small amounts, for instance, about 44 pounds at a time. The temperature employed is from 150- i" C. Generally speaking, the gauge pressure during the operation approximates 200 pounds at the maximum, and when reaction is complete. drops to zero, due to complete absorption of the ethylene oxide. When all the ethylene oxide has been absorbed and the reactants cooled, a second small portion, for instance, 44 more pounds of ethylene oxide, are added and the procedure repeated until the desired ratio of 15 pound moles of ethylene oxide to one pound mole of glycerol s obtained. This represents 660 pounds of ethylene oxide for 92 pounds of glycerol.

OXYETHYLATED GLYCEROL Example 2 The ratio of ethylene oxide is increased to 18 pound moles for each pound mole of glycerol. Otherwise, the same procedure is followed as in Example 1, preceding.

OXYETHYLATED GLYCEROL Example 3 The same procedure is followed as in the two previous examples, except that the ratio of ethylene oxide to glycerol is increased to 21 to one.

OXYETHYLATED GLYCEROL MALEATE Example 1 One pound mole of oxyethylated glycerol (1 to 15 ratio) prepared in the manner previously described is treated with one pound mole of maleic anhydride and heated at approximately C. for approximately thirty minutes to two hours. with constant stirring. so as to yield a monomaleate.

OXYETHYLATED GLYCEROL MALEA'rs Example 2 The same procedure is followed as in the preceding example, except that two moles of maleic anhydride are employed so as to obtain the dimaleate instead of the mono-maleate.

OXYETHYLATED GLYCEROL Marmara Example 3 The same procedure is followed as in the two preceding examples, except that three moles of maleic anhydride are employed so as to obtain the trimaleate.

- OxYsrHYLA'rED GLYCEROL MALEATE Example 4 The same procedure is employed as in the prethe formula R1(OH) mceding examples, except that oxyethylated glycerol (ratio 1 to 18) is substituted in place of oxy-.

preferably, detergent-forming acids which are liquid at ordinary temperature, and most especially, unsaturated fatty acids.

. Detergent-forming acids are monocarboxy acids having more than Band not over 32 carbon atoms, and characterized by thefac-t that they combine with alkalies such as caustic soda, caustic potash, ammonia, triethanolamine, and the like, to produce soap or soap-like materials. The best examples are, of course, the higher fatty acids, such as oleic acid, stearic acid, palmitic acid, etc. In addition to the higher fatty acids, other well known members of this class include resinic acids, abietic acids, naphthenic acids, and

acids obtained by the oxidation of petroleum hy-- drocarbons and commonly referred to as oxidized wax acids.

Generally speaking, the higher fatty acids are apt to contain from 12-14 carbonatoms as a lower limit, to 18-22 carbon atoms as an upper limit. Oxidized wax acids may contain as many as 32 carbon atoms. For the sake of brevity, reference will be made to superglycerinated fats, although it is understood that similar products obtained from other detergent-forming acids, as Well .as fatty acids, are just as acceptable.

Superglycerinated fats can be prepared by a number of well known procedures. One procedure is to react the fatty acid with a suitable polyhydric alcohol. Another procedure is to react an ester, for instance, a glyceride, with an excess of glycerol. Suchprocedure is sometimes referred to as reesterification. Other procedures include the use of ethylene oxide, ethylene chlorhydrin, glycerol monochlorhydrin, glycid .or the like. Since the manufacture of these. products is well known, particularly in view of their utility in a number-of industries, it does not appear that further comment is required. However, attention is directed to a trade pamphlet entitled Polyhydric Alcohol Esters, issued by the Glycol Products Company, 1940. This pamphlet describes numerous fractional esters derived from fatty acids which are particularly adaptable for use as reactants in the present instance.

It is to be noted that the higher fatty acids include blown fatty acids, or superglycerinated esters obtained from blown oils. As to the specific description of this particular type of material which may be used as a reactant, 'see U. S.

Patent N0. 2,208,509, dated July 16, 1940, to Blair and Boydstun. y

As herein used, the term polyhydricalcoho refersto aliphatic alcohols containing two or more hydroxyl groups, and is intended to include such compounds as glycerol, ethylene glycol, beta-methyl glycerol, 1,3 propanediol, pentamethylene glycol, alpha, beta, gamma pentanetriol, sorbitol, mannitol, and the like, and also the polyhydroxyether alcohols, such as diglycerol, triglycerol, tetraglycerol, diethylene glycol,

etc. Such polyhydric ether alcohols may also be produced by ether formation from two or more diiferent polyhydric alcohols to yield compounds, such as ethylene glycol monoglyceryl ether, 1,3 propanediol monoethylene glycol ether, diethylene glycol monoglyceryl ether, etc. Suitable polyhydroxy ether alcohols may also be produced from a polyhydric alcohol containing three or more hydroxyls and a monohydric alcohol. Examples of such compounds are glycerol monobutyl ether, glycerol monoalkyl ether, pentanetriol monoethyl ether, diglycerol monopropyl ether,

etc.

COMPLETED 'MoNoMERIc DERIVATIVE Example 1 One pound mole of a product of the kind described under the heading Oxyethylated glycerol maleate, Example 1 is reacted with one pound mole of ethylene glycol monoricinoleate, preferably in the absence of any high boiling hydrocarbon or inert solvent. However, if an inert vaporizing solvent is employed, it is generally necessary to use one which has a higher boiling range than xylene, and sometimes removal of such solvent might present a difficulty. In other instances, however, such high boiling inert vaporizing solvent, if employed, might be permitted to remain in the reacted mass and appear as a constituent or ingredient of the final product. In any event, our preference is to conduct the reaction in the absence of any such solvent and permit the reaction to proceed with the elimination of water. The temperature of reaction is about to 200 C. and the time of reaction about 20 hours.

COMPLETED MONOMERIC DERIVATIVE Example 2 The same procedure is followed as in Completed monomeric derivative, Example 1, preceding, except that the dimaleate described under the heading Oxyethylated glycerol maleate, Example 2" is used instead of the monomaleate.

CoMrLE'rEn MONOMERIC DERIVATIVE Example 3 The same procedure is followed as in the two preceding examples, except that the trimaleate is substituted for the monomaleate or. dimaleate in the two preceding examples.

COMPLETED MONOMERIC DERIVATIVE Example 4 The same procedure is followed as in Examples 2 and 3, immediatelypreceding, except that for each pound mole of the maleate, or each pound mole of the trimaleate, instead of using one pound mole of ethylene glycol monoricinoleate as a reactant, one employs two pound moles.

COMPLETED MoNoMERIcDERIvA'rIvE Example 5 CoMrLETEo MONOMERIC DERIVATIVE Example 6 ent instance, a more highly oxyethylated glycerol is employed, to wit, one involving the ratio of 1 to 18. (See Oxyethylated glycerol maleate, Example 4, preceding.)

COMPLETED MONOMERIC DERIVATIVE Example 7 COMPLETED MoNomERIc DERIVATIVE Example 8 Mono-olein is substituted for ethylene glycol monoricinoleate, in Examples 1 to 7, preceding.

COMPLETED MONOMERIC DERIVATIVE Example 9 Diethylene glycol monoricinoleate is substituted for ethylene glycol monoricinoleate, in Examples 1 to 7, preceding.

COMPLETED MONOMERIC DERIVATIVE Example 10 Propylene glycol monoricinoleate is substituted. for ethylene glycol monoricinoleate, in Examples 1 to 7, preceding.

The method of producing such fractional esters is well known. The general procedure is to employ a temperature above the boiling point of water and below the pyrolytic point of the reactants. The products are mixed and stirred constantly during the heating and esterification step. If desired, an inert gas, such as dried nitrogen or dried carbon dioxide, may be passed through the mixture. Sometimes it is desirable to add an esterification catalyst, such as sulfuric acid, benzene sulfonic acid, or the like.- This is the same general procedure as employed in the manufacture of ethylene glycol dihydrogen diphthalate. (See U. S. Patent No. 2,075,107, dated March 30, 1937, to Frasier.) A

Sometimes esterification is conducted most readily in the presence of an inert solvent, that carries away the water of esterification which may be formed, although as is readily appreciated, such water of esteriflcation is absent when such type of reaction involves an acid anhydride, such as maleic anhydride, and a. glycol. However, if water is formed, for instance, when citric acid is employed, then a solvent such as xylene may be present and employed to carry off the water formed. The mixture of xylene vapors and water vapors can be condensed so that the water is separated. The xylene is then returned to the reaction vessel for further circulation. This is a conventional and well-known procedure and requires no further elaboration.

In the previous monomeric examples there is a definite tendency, in spite of precautions, at least in a number of instances, to obtain polymeric materials and certain cogeneric by-products. This is typical, of course, of organic reactions of ly described, particularly a polymer whose molec ular weight is a rather small multiple of the molecular weight of the monomer, for instance, a polymer whose molecular weight is two, three, four, five, or six times the molecular weight of the monomer. Polymerization is hastened by the presence of an alkali, and thus in instances where it is necessary to have a maximum yield of the monomer, it may be necessary to take such precautions that the alkali used in promoting oxyethylation of glycerol, be removed before subsequent reaction. This, of course, can be done in any simple manner by conversion to sodium chloride, sodium sulfate, or any suitable procedure.

In the preceding examples of the Completed monomeric derivative, Examples 1 to 10, inclusive, no reference is made to the elimination of such alkaline catalyst, in view of the effectiveness of thelowmultiplepolymers as demulsifiers; Previous reference has been made to the fact that the carboxylic hydrogen atom might be variously replaced by substituents, including organic radicals, for instance, the radicals obtained from alcohols, hydroxylated amines, nonhydroxylated amines. polyhydric alcohols, etc. Obviously, the reverse is also true, in that a free hydroxyl group may be esterifled with a selected acid, varying from such materials as ricinoleic acid to oleic acid, including alcohol acids, such as hydroxy acetic acid, lactic acid, ricinoleic acid and also polybasic acids of the kind herein contemplated.

With the above facts in mind, it becomes obvious that whathas been previously said as to polymerization, with the suggestion that byproducts or cogeneric materials were formed, may be recapitulated with greater definiteness, and one can readily appreciate that the formation of heat-rearranged derivatives or compounds must take place to a greater or lesser degree. Thus, the products herein contemplated may be characterized by being monomers of the type previously described, or esterification polymers, or the heat-rearranged derivatives of the same, and thus including the heat-rearranged derivatives of both the polymers and esterification monomers, separately and jointly. Although the class of materials specificallycontemplated in this instance is a comparatively small and narrow class of a broad genus, yet it is obviously impossible to present any adequate formula which would contemplate the present series in their complete amidiflcation, except in a manner employed in the hereto appended claims.

Although the products herein contemplated varyso broadly in their characteristics, i. e., monomers through sub-resinous polymers, soluble products, water-emulsifiable oils or compounds, hydrotropic materials, balsams, subresinous materials, semi-resinous materials, and the like, yet there is always present the characteristic unitary hydrophile structure related back to the oxyalkylation. particularly the oxyethylation of the glycerol used as the raw material. As hereinafter indicated, in practicing our process, the demulsifler may be added to the emulsion at the ratio of 1 part in 10,000, one part in 20,000, 1 part in 30,000, or for that matter,

1 part in 40,000. In such ratios it well may be that one can not diflerentiate between the solubility of a compound completely soluble in water in any ratio, and a semi-resinous product apparently insoluble in water in ratios by which ordinary insoluble materials are characterized. However, at such ratios the importance must reside in interfacial position and the ability to usurp, preempt, or replace the interfacial position previously occupied perhaps by the emultion altered wettability and the like. As to amidification polymers, for instance, where Z is a polyamineamide radical, see what is said subsequently.

'COMPLETED POLYMERIC Dams-lavas Incummc HEAT-REARRANGED Cocamsas Example 1 t A material of the kind described previously under the heading Completed monomeric derivative, Example 3," is heated at a temperature of approximately 220-240 0., with constant stirring, for a period of two to 60 hours,-so as to eliminate sufiicient water, in order to insure that the resultant product has a molecular weight approximately twice that of the initial raw material.

COMPLETED POLYMERIC DERIVATIVES Incummc HEAT-REARRANGED Coo-sna s Example 2 The same procedureis followed as in the preceding example, except that polymerization is continued, using either a somewhat longer reaction time, or it may be, a somewhat higher temperature, or both, so as to obtain a material having a molecular weight of approximately three or four times that of the initial product.

COMPLETED POLY 'MIRIO DERIVATIVES INCLUDING I-IsAr-Riummcsn Cocannns Ewample 3 The same procedure is followed as in Examples 1 and 2, preceding, except that one employs reactants derived from more highly oxyethylated glycerol, or fromgoxyethylated ethylene glycol monoricinoleate,or from an intermediate involving both materials.

Corrrtsrso Ponmiuc DERIVATIVES Incnunmc Hus-mamas Cocmmis Example 4 The same procedure is followed as in Examples 1.. to 3, preceding, except that one polymerizesa mixture instead of a single monomer, for instance, a mixture of materials of the kind described in Completed monomeric derivative, Example 3, and -in Completed monomeric derivastantly during the reaction.

such reactants as raw tive, Example 4, are mixed in molecular proportion and subjected to polymerization in the manner indicated in the previous examples.

It is understood, of course, that the polymerized product need not be obtained as a result of a two-step procedure. In other words, one need not convert the reactants into the monomer and then subsequently convert the monomer into the polymer. The reactants may be converted through the monomer to the polymer in one step. Indeed, the formation of the monomer and polymerization may take place simultaneously. This is especially true if polymerization isconducted in the absence of a liquid such as xylene, as previously described, and if one uses a comparatively higher temperature, for

instance, approximately 200 C. for polymeriza- Thus, one pound mole of oxyethylated tion. glycerol maleate of the kind described, ratio 1 to 15 up to 1 to 21, is mixed with three moles of ethylene glycol monoricinoleatefand" reacted for twenty hours at approximately 200, until the mass is homogeneous. It is stirred con- Polyfunctionality may reside in dehydration (etherization) of two hydroxyl groups attached to dissimilar molecules.

The fact that the polymerized and heat-rearranged prcducts can be made in a single step, illustrates a phenomenon which sometimes occurs either in such instances where alcoholic bodies of the kind herein illustrated are contemplated as reactants, or where somewhat kindred alcoholic bodies are employed. The reactants may be mixed mechanically to give a homoge neous mixture, or if the reactants do not mixto give a homogeneous mixture, then early in the reaction stage there is formed, to a greater or lesser degree, sumcient monomeric materials so that a homogeneous system is present. Subsequently, as reaction continues, the system may become heterogeneous and exist in two distinct phases, one being possibly an oily body of moderate viscosity, and the other being a heavier material, which is' sticky or sub-resinous in nature. In many instances it will be found that the thinner liquid material isa monomer and the more viscous or resinous material is a polymer, as previously described. Such product can be used for demulsifl cation by adding a solvent which will mutually dissolve the two materials, or else, by separating the two heterogeneous phases and employing each as if it were a separate product of reaction.

Conventional demulsifying agents employed in the treatment of oil field emulsions are used as such, or after dilution with any suitable solvent,

.such as water; petroleum hydrocarbons such as gasoline, kerosene, stove ofl, a coal tar product such asbenzene, toluene, xylene, tar acid oil, cresol, anthracene oil, .etc. Alcohols, particularly aliphatic alcohols, such as methyl alcohol, ethyl-alcohol, denatured alcohol, propyl alcohol, butyl alcohol, hexyl alcohol, octyl' alcohol,

,etc., may be employed as diluents. Miscellaneous solvents, such as pine oil, carbon tetrachloride,

sulfur dioxide extract obtained in the-refining of I petroleum, -etc., may be employed as diluents.

Similarly, the material or materials herein described, may be admixed with one or more of the solvents customarily usedin connection with conventional demulsifying agents, provided that such compounds are compatible. They will be compatible with the hydrophile type of solvent in all instances. Moreover, said material or materials may be used alone, or in admixture with other suitable well known classes of demulsifying agents.

It is well known that conventional demulsifying agents may be used in a water-soluble form, or in an oil-soluble form, or in a form exhibiting both oil and water-solubility. Sometimes they may be used in a form which exhibits relatively limited oil-solubility. However, since such reagents are sometimes used in a ratio of l to 10,000, or 1 to 20,000, or even 1 to 30,000, S h an apparent insolubility in oil and water is not significant, because said reagents undoubtedly have solubility within the concentration employed. This same fact is true in regard to the material or materials herein described, except that they are invariably water-soluble.

, We desire to point out that the superiority of the reagent or demulsifying agent contemplated in our herein described process for breaking petroleum emulsions, is based upon its ability to treat certain emulsions more advantageously and at a somewhat lower cost than is possible with other available demulsifiers, or conventional'mixtures thereof. It is believed that the particular demulsifying agent or treating agent herein described will find comparatively limited application, so far as the majority of oil field emulsions are concerned; but we have found that such a deabove described is brought into contact with or caused to act upon the emulsion to be treated, in any of the various ways, or by any of the various apparatus now generally used to resolve or break petroleum emulsions with a chemical reagent, the above procedure being used either alone, or in combination with other demulsirying procedure, such as the electrical dehydration process.

The demulsifier herein contemplated may be employed in connection with what is commonly known as down-the-hole procedure, i. e., brin ing the demulsifier in contact with the fluids of the well at the bottom of the well, or at some point prior to their emergence. This particular type of application is decidedly feasible whenthe demulsifier is used in'connection with acidification of calcareous oil-bearing strata, especially if suspended in or dissolved in the acid employed for acidification.

cognizance must be taken of the fact that the surface of the reacting vessel may increase or decrease reaction rate and degree of polymerization, for instance, an iron reaction vessel, speeds up reaction and polymerization, compared with a glass-lined vessel.

As has been previously indicated, the sub-genus employed as an alcohol in the present instance is one of a series of alcoholic compounds which are contemplated in our co-pending applications Serial Nos. 447,151; 447,153; 447,154; 447,155; 447

of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifier comprising a member of the class consisting of monomers, sub-resinous esterification polymers,

1 and cogeneric sub-resinous heat-rearranged derivatives of the monomers and aforementioned polymers, separately and jointly, and of the following formula:

in which R is the carboxyl-free radical of a polybasic carboxy acid having not over 8 carbon atoms; R1 is a water-insoluble hydroxylated fractional ester radical having as an integral part (a) a polyhydric alcohol radical having at least two carbon atoms and not more that 12 carbon atoms; and (b) a detergent-forming monocarboxy radical having 8 and not more than 32 carbon atoms; Z is an acidic hydrogen atom equivalent including the acidic hydrogen atom itself; 11. represents the numerals 2 to. 4; n represents the numerals 3 to 10; n" represents the numerals 1 to 2; :n represents the numerals 0 to 2; :1 represents the numerals 0 to.2; 2 represents the numerals l to 3; m represents the numerals 0 to 1; and 3/ represents the numerals 1 to 2. I

2. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a. demulsifier comprising a member of the class consisting of monomers, sub-resinous esterification polymers, and cogeneric sub-resinous heat-rearranged derivatives of the monomers and aforementioned polymers, separately and jointly, and of the following formula:

in which R is a carboxyl-free radical of a dibasic carboxy acid having not over 6 carbon atoms; R1 is a water-insoluble hydroxylated fractional ester radical having as an integral part (a) a polyhydric alcohol radical having at least 2 carbon atoms and not more than 12 carbon atoms; and (b) a detergent-forming monocarboxy radical having at least 8 carbon atoms and not more than 32 carbon atoms; Z is an acidic hydrogen atom equivalent including the acidic hydrogen atom itself; 11. represents the numerals 2 to 4; n represents the numerals 3 to 10; 3: represents the numerals 0 to 2; 11 represents the numerals 0 to 2;

( i-HMO) "'00 C R and 2 represents the numerals 1 to 3.

3. A'process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifier comprising a member of the class consisting of monomers, sub-resinous esterification polymers, and cogeneric sub-resinous heat-rearranged derivatives of the monomers and aforementioned polymers, separately and jointly, and of the following formula:

in which R is a carboxyl-free radical of a. dibasic carboxy acid having not over 6 carbon atoms; R1 is a. water-insoluble hydroxylated fractional ester radical having as an integral part (a) a polyhydric alcohol radicalhaving at least atoms; and (b) a detergent-forming monocarboxy radical havingat least 8 carbon atoms and not more than 32 carbon atoms; 2 is 'anacidichydrogen atom equivalent including the ,acidic' hydrogen atom itself; n represents the numerals 3 to 10; :2: represents the numerals to 2; y represents the numerals 0 to 2; and 2 represents the numerals 1 to 3.

4. A process of breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a de'mulsi-' iler comprising a polar member of the class consistlng of monomers, sub-resinous esteriflcation polymers, and cogeneric sub-resinous heat-rearranged derivatives of the monomers and aforementioned polymers, separately and jointly, and of the following formula:

r 2 carbon atoms and not more than 12 carbon and aforementioned polymers, separately and jointly, and 'of'the following formula:

, KCIHIO MOOCRCQOZ13 CaI ROV- KCZHA M'HL V [(CQH40)n'OOCRCOORl1r v m which'Ris a carbonyl-free radical of'a dibasic carboxy acid having not over 6 carbon-atoms; R1 'is a water-insoluble hydroxylated' fractional ester radical havinghasan integral part (M a polyhydric alcohol radical having atleast2 carbon atoms and not more than 12 carb toms;

and (b) a higher fatty acid radical'ha ng at least 8 and not more than 18 carbonatojms; Z

is an acidic hydrogen atom equivalent including the acidic hydrogen atom itself; 11' represents the numerals 3 to 10; :1; represents the numerals 0 to 2; y represents the numerals 0 to 2; and 2 represents the numerals 1 to 3. I

7. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subin which R is'a carboxyl-free radical of a di- 7 basic carboxy acid having not over 6' carbon atoms; R1 is a water-insoluble hydroxylated fractional ester radical having asan integral part (a) a polyhydric alcohol radical havlngiat least 2 carbon atoms and not more than 12 carbon atoms; and (b) a detergent-forming monocarboxy radical having at least. 8 carbon atoms and not more than 32 carbon atoms; Z is an acidicaforementioned polymers, separately and jointly,

hydrogen atom equivalent including the acidic hydrogen atom itself; n represents the numerals 3 to 10; :r represents the numerals 0 to 2; 1! represents the numerals 0 to 2; and 2 represents the numerals 1 to 3.

5. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to th action of a demulsifier comprising a polar acidic member of the class consisting of monomers, sub-resinous esteriflcation polymers, and cogeneric sub-resinous heat-rearranged derivatives of the monomers and aforementioned polymers, separately and jointly, and of the following formula:

hydrogen atom' itself; n represents the numerals 3 to 10; 2: represents the numerals 0 to 2; yr represents the numerals 0 to 2: and 2 represents the numerals 1 to 3.

6. A process for breaking petroleum emulsions of the watcr-in-oil type, characterized by subjecting the emulsion to the action of a demulsifier comprising a polar acidic member of the class consisting of monomers, sub-resinous esteri i lcation polymers, and cogeneric' sub-resinous heat-rearranged derivatives of the monomers jecting themulsion to the actionof a demulsifler comprising a polarnacidic member of theclass consisting of monomers, sub-resinous esterification polymers, and cogeneric sub-resinous heat-rearranged derivatives of the monomers and and of the following formula:

[(oznio toocncoozp.

in which R is a carboxyl-free radical of a dibasic carboxyacid having not over 6 carbon atoms; R1 is a water-insoluble hydroxylated fractional ester radical having as an integral part (a) a polyhydric alcohol radical having at least 2 carbon atoms and not more than 12 carbon atoms; and (b) an unsaturated higher fatty acid radical having at least 8 and not more than 18 carbon atoms; Z is an acidic hydrogen atom equivalent including the acidic hydrogen atom itself; n represents the numerals' fi .to 10; :1: represents the numerals 0 to 2; y represents the-numerals 0 to 2; and 2 represents the numerals 1 to'3.

8. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifier comprising a polar acidic member of the class consisting of monomers, sub-resinous esterification polymers, and cogeneric sub-resinous heat-rearranged derivatives of the monomers and aforementioned polymers, separately and jointly, and of the following formula:

' in which R is a carboxyl-free radical of a dibasic carboxy acid having not over 6 carbon atoms; R1 is a water-insoluble hydroxylated fractional ester radical having as an integral part (a) a polyhydric alcohol radical having at least 2 carcarboxy acid having not over 6 carbon atoms; and '(b) a ricinoleic acid radical; Z is an acidic hydrogen atom equivalent including the acidic hydrogen atomitself; -n' represents the-numerals 3 to 10; :1: represents the numerals 0 to 2; y represents the numerals 0 to 2; and 2 represents the numerals l to 3. 1

' MELVIN DE GROO'IE.

BERNHARD KEISER. 

